General fact: 47847 is a number for which we're missing a fact (submit one to numbersapi at google mail!).
Mathematical fact: 47847 is a boring number.
Trivia: 47847 is an unremarkable number.
Historical date: December 31st is the day in 1879 that Thomas Edison demonstrates incandescent lighting to the public for the first time, in Menlo Park, New Jersey.